The effectiveness of ethylene oxide (EtO) for destroying pathogens in the case of heat and moisture sensitive materials has led to its wide spread use in sterilization processes. Products that are often sterilized with EtO include medical equipment, medical supplies and pharmaceutical produces. Hospitals using EtO sterilizers are of particular interest in this program. In 1983 OSHA reported that EtO was used in 7,700 sterilizers in 6,300 hospitals in the U.S. In consideration of the potential risk to public health posed by uncontrolled air emissions of EtO, the EPA placed EtO on its list of hazardous air pollutants (HAP) and established a regulation for EtO emissions from commercial sterilizers. Citing cost effectiveness issues for small emission sources, it specifically exempted hospitals from the rule, despite their statement that hospital sterilizers emit substantial percentage of EtO emissions. EPA can change its position at any time. Compact membrane Systems (CMS) has identified a novel membrane system that provides a procedure to actually recover the EtO for reuse. The concept is that the value of the recovered EtO will either be greater than the cost of recovering or that the net cost for recovery is at least 30% less than present abatement systems. In Phase I we will build a membrane system and demonstrate the capability of recovering the EtO. This will then be followed by performing a detailed economic evaluation which will validate the feasibility of doing this economically. CMS has established strong business relationships with major membrane companies and industrial gas companies. These relationships will help in successfully completing this program and subsequent commercialization.